2-(aryloxy)-2-thiazolinium compounds

ABSTRACT

2-(Aryloxy)-2-thiazolinium hydrochlorides (A) and chlorides (B), useful as pesticides, are prepared by reacting, for (A) compounds, an N-unsubstituted aziridine with an aryloxythiocarbonyl chloride; and by reacting, for (B) compounds, an Nalkyl- or an N-arylaziridine with an aryloxy-thiocarbonyl chloride. The 2-(aryloxy)-2-thiazolines are liberated from their thiazolinium hydrochlorides by reaction with aqueous base.

United States Patent Tomalia [451 Oct. 10,1972

[54] 2-(ARYLOXY)-2-THIAZOLINIUM COMPOUNDS I [72] inventor: Donald A.Tomalia, Midland, Mich.

[731 Assignee: The Dow Chemical Company,

Midland, Mich.

[221 Filed: Oct. 2, 1967 ml Appl. No.2 67l,957

[52] US. Cl. ..260/306.7, 260/455 R, 424/270 [51] Int. Cl. ..C07d 91/24[58] Field of Search ..260/306.7

[56] References Cited UNITED STATES PATENTS 3,108,114 10/1963 Krespan..260/307 3,551,417 12/1970 Symon et a] ..260/307 3,247,220 4/1966 Ham..260/307 OTHER PUBLlCATlONS Gembitskii et al., Russian Chem. Reviews,Vol. 35, page 114 (1966) (Eng. Ed.)

Iwakura et al., J. Org. Chem, Vol. 32, pages 2362- 2364 (1967) PrimaryExaminer-Alton D. Rollins Attorney-Griswold & Burdick, John L. Spaldingand Theodore Post ABSTRACT 2-(Aryloxy)-2-thiazolinium hydrochlorides (A)and chlorides (B), useful as pesticides, are prepared by reacting, for(A) compounds, an N-unsubstituted aziridine with an aryloxy-thiocarbonylchloride; and by reacting, for (B) compounds, an N-alkylor an N-arylaziridine with an aryloxy-thiocarbonyl chloride. The2-(aryloxy)-2-thiazolines are liberated from their thiazoliniumhydrochlorides by reaction with aqueous base.

9 Claims, No Drawings thiazolinium hydrochloride results when anN-unsubstituted aziridine co-reactant is used, while a 2- thiazoliniumchloride results when one of the same thiocarbonyl chlorides is refluxedwith an N-substituted (l-substituted) aziridine co-reactant, which maybe substituted also in the,2-, 2-, or 2,3-positions.

in the process of this invention, an aryloxythiocarbonyl chloride havingthe formula R-O-C(S)Cl, wherein R represents a phenyl group which mayhave one to three substituents of the group of F, Cl,'Br, N OCH, or CN,is reacted with an aziridine having the formula ER -CR 'R -Q-IR, whereinR represents H (when a thiazolinium hydrochloride is desired), orphenyl, one to four carbon alkyl, aralkyl, i.e., aryl (one to fourcarbon alkyl) wherein aryl is phenyl or naphthyl, when a thiazoliniumchloride is desired and R and R individually represent H, phenyl, andone to four carbon alkyl, in either case, whereby thiazoliniumhydrochlorides or thiazolinium chlorides are formed. The reaction isrepresented by the following equation:

wherein R has the significance indicated above.

The reaction between the aryloxythiocarbonyl chloride with an aziridineto form a 2-thiazolinium hydrochloride or chloride is carried out byheating the reactants at a temperature ranging between ca. 75 and 150C.,advantageously in the presence of one or more aprotic non-reactivesolvents such as chlorinated hydrocarbons, e.g., carbon tetrachloride,methylchloroform and chlorobenzene and aliphatic nitriles such asacetonitrile and propionitrile, since the reaction is exothermic,advantageously by gradual or dropwise addition of a solution of theaziridine in such a solvent to a stirred solution of thearyloxythiocarbonyl chloride in such a solvent. The addition is carriedout over a period of time sufficient to add the aziridine, usually up toabout one hour, followed by refluxing the reaction mixture with stirringat ca. 75-450C. for an additional period of time sufficient to form thedesired reaction product. The progress of the reaction can be followedspectroscopically. It is substantially completed, usually, in up toabout two hours. After cooling the reaction mixture to room temperature,solid product is filtered off. It is recrystallized from an appropriatesolvent or mixture of solvents, depending upon the solubility of theproduct, such as a mixture of diethyl ether and methylene chloride, oracetonitrile. Alternately, some products can be slurried with acetoneand filtered. The acetone dissolves impurities. Products are identifiedby carbon, hydrogen and nitrogen analyses and by nuclear magneticresonance (n.m.r.) and infrared (IR) spectra confirmation. The 2-thiazoline free base is liberated from the 2-thiazolinium hydrochlorideby reaction with an equimolar proportion of an aqueous base, e.g., analkali metal carbonate, bicarbonate or hydroxide, followed by extractionof the aqueous mixture with diethyl ether or other solvent in which theproduct is soluble, removal of solvent from the extract phase anddistillation to recover product.

The amounts of the reactants to be employed are not critical, some ofthe desired product being obtained when employing any amount of saidreactants. The reaction consumes the reactants in substantiallyequimolar proportions and the use of the starting materials in suchproportions is preferred.

Representative of the aryloxythiocarbonyl chlorides useful in thepractice of this invention are phenoxythiocarbonyl chloride,3,4-dichlorophenoxythiocarbonyl chloride,2,4,5-trichlorophenoxythiocarbonyl chloride,2,6-dichlorophenoxythiocarbonyl chloride and such of their analogs asdescribed above.

Representative of the aziridines useful in the practice of thisinvention are aziridine, l-phenylaziridine, lethylaziridine,l-phenethylaziridine, 2,2- dimethylaziridine, 2,2-diethylaziridine andl-ethyl-2,2- dimethylaziridine.

The following examples describe completely representative specificembodiments and the best modes contemplated by the inventor for carryingout the inventive embodiments of the process and products hereinafterclaimed.

Example 1 2-Phenoxy-2-thiazolinium hydrochloride To a stirred solutionof phenoxythiocarbonyl chloride (17.25 g., 0.10 mole) in 100 ml. ofcarbon tetrachloride was added dropwise a solution of aziridine (4.3 g.,0.10 mole) in 25 ml. of the same solvent. The addition was carried outover a period of onehalf to 1 hour during which time an exotherm wasobserved. The reaction mixture was refluxed for l2 hours at about 80C.while stirring. After cooling to room temperature, the solid wasfiltered off. A melting point determination gave an m.p. of l50155C.Recrystallization from a mixture of diethyl ether and methylene chloridegave an analytical sample of white crystals melting at l60l63C. Then.m.r. spectrum was consistent with the proposed structure. The IRspectrum displayed a characteristic band at 1736 cm OFK) A nitrogenanalysis for C H NOS.HCl gave: Calc.

Nitrogen: 6.50 percent Found Nitrogen: 6.27 percent.

Example 2 2-Phenoxy-2-thiazoline The free base of the product of Example1 was obtained by adding 11.4 g., 0.053 mole, of 2-phenoxy-2-thiazolinium hydrochloride to a stirred solution of sodium hydroxide(2.1 g., 0.053 mole, in 55 ml. of water) in small portions. A lightyellow oil separated. The aqueous mixture was extracted with 3 X ml. ofdiethyl ether, the combined extracts were dried over anhydrous MgSO,followed by removal of the solvent by use of vacuum at room temperature.The product was obtained as a light yellow oil. Distillation of thismaterial gave pure product, b.p. l24-l25C./ 1.5 mm. The

119 -9391? Rspssttaw ssssra st rt wi has w w Example 33-Ethyl-2-phenoxy-2-thiazolinium chloride A solution of l-ethylaziridine(7.1 g., 0.10 mole) in 25 ml. of methylchloroform was added dropwise toa stirred solution of phenoxythiocarbonyl chloride (17.25 g., 0.10 mole)in 100 ml. of the same solvent. The addition was made over a period ofone-half hour and was accompanied by a moderate exothermic reaction. Asubstantial amount of white solid precipitated out during this time.After refluxing for 3 hours the reaction mixture was cooled and filteredin a dry box. A tan crystalline product was obtained which had a m.p. ofl45l 50C. This material was hygroscopic and had tobe handled underanhydrous conditions. Recrystallization from 95 percent ethanol gavenice white plates, m.p. l491 505C. The IR spectrum showed acharacteristic absorption band at -174O cm"' and the n.m.r. spectrumexhibited a pattern which was consistent with the product3-ethyl-2-phenoxy-2- thiazolinium chloride. Elemental analysis indicatedthe salt was a monohydrate. Analysis for C H CI NOS.H O:

Calc.: C, 50.5 percent; H, 6.15 percent; N, 5.35 percent.

Found: C, 50.6 percent; H, 6.00 percent; N, 5.31 percent.

Example 4 3-Phenethyl-2-phenoxy-2-thiazolinium chloride In a similarmanner as described in Example 3, the above compound was prepared byreacting lphenethylaziridine (14.7 g., 0.10 mole) withphenoxythiocarbonyl chloride (17.25 g., 0.10 mole). The crude productwas obtained as tan, hygroscopic crystals, m.p. 133l35C.Recrystallization from 95% ethanol gave a white crystalline product,m.p. 142-l4 3C. The IR spectrum displayed a characteristic absorptionband at -1735 cm Elemental analysis indicated the salt was obtained as amonohydrate. Analysis for C H CI NOSE- O:

Calc.: C, 60.43 percent; H, 5.96 percent; N, 4.14 percent.

Found: C, 60.70 percent; H, 5.84 percent; N, 4.12 percent.

Example 5 2-(3,4-Dichlorophenoxy)-thiazolinium hydrochloride Theprocedure of Example 1 was repeated, using as reactants3,4-dichlorophenoxythiocarbonyl chloride, 0.075 "mole, and aziridine,0.075mole, dissolved, respectively, in 200 ml. and in 100 ml. ofacetonitrile.

An immediate exothermic reaction raised the temperature of the reactionmixture to 68C. The reaction mixture was thereafter heated to reflux andrefluxed for 25 minutes. At this time a white gelatinous solid suddenlyseparated and set up solid. Heat was removed and the reaction flask wasimmersed in an ice bath. The resulting crystals were collected on afilter, air dried and recrystallized from acetonitrile to give whitecrystals having a m.p. of 159-l60C. N.m.r. and IR spectra continued thestructure for the above stated product.

Example 6 2-( 3,4-Dichloro-phenoxy)-3-( 2-phenethyl)-v thiazoliniumchloride The procedure of Example 5 was repeated, using as reactants3,4-dichlorophenoxythiocarbonyl chloride, 0.075 mole, andN-phenethylaziridine, 0.075 mole. After crystallization fromnitromethane, the white product melted at l20-l20.5C. N.m.r. confirmedthe structure for the above stated product, a definite peak for waterbeing observed. Combustion analysis checked for the monohydrate.Analysis. for C H CI NO5.H2O:

Calc.: C, 50.20 percent; H, 4.46 percent; N, 3.44 percent. Found: C,49.8 percent; H, 4.37 percent; N, 3.38 percent.

Example 7 2-(2,4,5-Trichlorophenoxy)-3-( 2- phenethyl)-thiazoliniumchloride The procedure of Example 5 was repeated, using as reactants2,4,5-trichlorophenoxythiocarbonyl chloride, 0.075 mole, andN-phenethylaziridine, 0.075 mole, and acetonitrile as solvent. Productcrystals were filtered, washed with toluene and acetonitrile and a m.p.of l98l99C. determined. N.m.r. and IR spectra were consistent with theabove stated product.

Example 8 2-( 2,6-Dichlorophenoxy)-3-( 2-phenethyl thiazolinium chlorideThe procedure of Example 5 was repeated, using as reactants2,6-dichlorophenoxythiocarbonyl chloride, 0.075 -mole, anclN-phenethylaziridine, 0.075 mole.

After overnight cooling, the, reaction flask contents were solid. CCL,was added to the greasy product, and

after filtration the solids were slurried with acetone, filtered, dried,and a m.p. of l72-l73C. was determined. The n.m.r. spectrum wasconsistent with the above stated product.

The products of the present invention are useful as pesticides. In suchapplications, the unmodified products can be used as such. Generally, itis preferred to use the products of this invention in the form of acomposition comprising one or more products and one or more aids oradjuvants, such as water, organic sol-. vents, surfactants, inert,particulate solids, and the like. The products of this invention arealso useful in aerosol compositions.

In representative operations, a solution of 50 ml. of water containing50 p.p.m. of the compound of Example 2 was prepared and to it was addedabout 50 3-day old yellow fever mosquito larvae. After 3 days exposure,a 98 percent kill of the larvae was observed. In the absence oftoxicant, a control showed no kill of larvae.

A series of culture media heavily infested with ova of Haemonchus spp.,Trichostrongylus spp., Cooperia spp., Ostertagia spp., Esophagostomumspp. and Bunostomum spp., derived from feces of infested calves, wereprepared. Half of the culture media contained 300 p.p.m. of the compoundof Example 4, the other half serving as control. The cultures wereincubated at 26-28C. for 5 days, then examined microscopically forliving larvae. The percent kill for the cultures containing the testcompound was 100 percent. The control was heavily infested with larvaeof the named species.

What is claimed is:

l. A 2-thiazolinium compound of the group consisting of2-phenoxy-2-thiazolinium hydrochloride, 3-ethyl-2-phenoxy-2-thiazolinium chloride, 3-phenethyl-2-phenoxy-2-thiazolinium chloride, 2-(3,4- dichlorophenoxy)-thiazoliniumhydrochloride, 2-(3,4- dichlorophenoxy)-3-(2-phenethyl)-thiazoliniumchloride, 2-( 2,4,S-trichlorophenoxy)-3-( 2-phenethyl thiazoliniumchloride and 2-(2,6-dichlorophenoxy)-3-

2. A 2-thiazoline compound which is 2-phenoxy-2-thiazoline.
 3. Thecompound of claim 1 which is 2-phenoxy-2-thiazolinium hydrochloride. 4.The compound of claim 1 which is 3-ethyl-2-phenoxy-2-thiazoliniumchloride.
 5. The compound of claim 1 which is3-phenethyl-2-phenoxy-2-thiazolinium chloride.
 6. The compound of claim1 which is 2-(3,4-dichlorophenoxy)-thiazolinium hydrochloride.
 7. Thecompound of claim 1 which is2-(3,4-dichlorophenoxy)-3-(2-phenethyl)-thiazolinium chloride.
 8. Thecompound of claim 1 which is2-(2,4,5-trichlorophenoxy)-3-(2-phenethyl)-thiazolinium chloride.
 9. Thecompound of claim 1 which is2-(2,6-dichlorophenoxy)-3-(2-phenethyl)-thiazolinium chloride.